Till recently Mongolia was a communist nation under the powerful influence of Soviet Russia. In the 1990's a democratic revolution took place which resulted in the country changin from a communist nation to a democratic one. Since religion was disouraged under communism, very few citizens were interested in joining the buddhist clergy and thus both interest as well as influence of the religion declined. After democracy was set-up, the buddhist monastaries started becoming more active to serve the local populace. The churches in the west (esp. America) knew that this is a golden opportunity to buy souls (convert people) using inducements like money. The article below shows how effective this cultural and religios colonization has been to destroy the culture of the native people and cause social unrest.
"Byambajav says he is most concerned about unregistered Christian groups, which he says indoctrinate children, convince Buddhists to burn religious articles and even destroy stupas (a mound-like structure that symbolizes enlightenment). "There is no control over these groups and no one is paying attention to what they are doing.""